More than 18 million Americans suffer from diabetes. But, some may not be aware of the serious damage it can have on the eyes. With more than 5.3 million Americans already diagnosed, diabetic retinopathy is the leading cause of new cases of blindness in people aged 20 to 74.

Diabetic retinopathy weakens the small blood vessels in the retina. Retinal blood vessels can break down, leak, or become blocked, impairing vision over time.

Prevent Blindness America (PBA), a non-profit organization dedicated to preserving sight, has created an online resource for patients and doctors to learn more about diabetic retinopathy. The Web site, www.preventblind ness.org/diabetes, offers free information on the disease, including symptoms, risk factors and treatment options. It also provides an easy-to-use quiz to determine the likelihood that one will lose his or her sight from diabetic retinopathy, and a virtual simulation of the affects of the disease on the visual field. The site was made possible by a grant from Eli Lilly and Company.